The algal-containing coarse granules are squamules. [The similarly red-tipped (but a deeper shade of red, not a scarlet red as here) Cladonia macilenta has areas of powdery soredia instead and is green when wet, whereas Cladonia floerkeana is grey even when wet].

Nearby surfaces are usually also covered in the squamules, being the means by which it proliferates.

Easily mis-identified as : Cladonia polydactyla and with Cladonia macilenta, both are red-tipped, but the red of C. floerkeana is more scarlet than the deeper red of Cladonia macilenta. Also Cladonia polydactyla is less often branched, usually thinner and longer and greyer than C. floerkeana. [The species list for Duddon Mosses lists only the above Cladonia floerkeana and Cladonia portentosa (= C. impexa), Cladonia pyxidata and Cladonia conioerea, so your Author is almost certain that the ID is spot on here].